Continental Europe shares a standardized two prong live plug design, however there are 5 different mechanisms used for grounding these plugs for high powered electrical devices. As most high power electrical devices, such as refrigerators and stoves, are often stationary, no need for a plug which satisfies the grounding design for more than two of these receptacle types has existed. For most small appliances, which require no grounding, a simple Europlug is used. This plug is standard across continental Europe. For grounded adapters, currently most often an interface is used which has a female face that accepts the plug type of the appliance, and a male face which has the correct design to insert into the desired receptacle. Another method is used with simple Europlug designs, in which a case is closed around the plug. Inside of this case are connectors which connect to the two live lines of the Europlug. These lines connect to prongs on the outside of the case, which are of the desired plug type, thus adapting the plug to the desired receptacle. These methods of adaption are suitable for infrequent, predetermined travel, so that one can be sure to have the correct plug type. However, plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs) will change this standard of travel infrequency and in the future, other electronics requiring grounding.
With the entrance of PHEVs and EVs into the commercial automotive market, the first high powered electrical devices requiring grounding while engaged with the grid were created. These vehicles have the ability to cross the borders of plug standards with high frequency and ease. High volume projection of PHEV and EV penetration is leading to a new requirement in AC plug design. In order to minimize the number of parts and products that must be offered to accompany a vehicle or current or later developed portable grounded electronics, a new design is necessary.
Accordingly, it is desirable to provide a charging system with an electrical plug or adapter having variable grounding that meets the requirements of all continental European plug design standards in a single plug design.